A Quantitative Trait Locus Associated With Cognitive Ability in Children

Quantitative trait loci (QTLs) associated with general cognitive ability ( g ) were investigated for several groups of children selected for very high or for average cognitive functioning. A DNA marker in the gene for insulin-like growth factor-2 receptor (IGF2R) on Chromosome 6 yielded a significantly greater frequency of a particular form of the gene (allele) in a high- g group (.303; average IQ = 136, N = 51) than in a control group (.156; average IQ = 103, N = 51). This association was replicated in an extremely-high- g group (all estimated IQs > 160, N = 52) as compared with an independent control group (average IQ = 101, N = 50), with allelic frequencies of .340 and .169, respectively. Moreover, a high-mathematics-ability group ( N = 62) and a high-verbal-ability group ( N = 51) yielded results that were in the same direction but only marginally significant ( p = .06 and .08, respectively).     

The Influence of Gender and Parental Attitudes on Preschool Children's Interest in Babies: Observations in Natural Settings

This paper reports on two studies of parents'observations of their preschool children's interactions with infants. In Study 1 parents observed 69 3- and 5-year-old white children with three nonsibling infants whom the children encountered during their daily lives. In Study 2 parents observed 46 3- to 6-year-old primarily white children with three nonsibling infants and completed measures of their own gender-related child-rearing attitudes.Consistent with findings from previous laboratory research, this research in naturalistic settings found girls to show more interest in, more nurturance toward,and more interaction with babies than did boys. In Study 2, children whose parents had traditional gender-stereotyped attitudes were more likely to show this gender difference than children whose parents had more egalitarian child-rearing attitudes.     

Effects of form rotation on the speed of classification: the development of shape constancy

Ss classified a test form as matching or not matching one of a set of memorized forms relative to which the test forms were rotated up to 90 deg. “Match” reaction times increased monotonically with both number of forms memorized and degrees of rotation. Disappearance of the rotation effect after practice was attributed to a change from considering rotational information during comparison to comparing rotation invariant features. The change in strategy is considered an indicant of the development of shape constancy. Time taken to memorize the patterns increased linearly with the size of the memory set, justifying interpretation of the RT effects in terms of comparison time differences rather than differences in memorial specification of the patterns.     

The teacher as observer and experimenter in the modification of disputing and talking-out behaviors

Disputing and talking-out behaviors of individual pupils and entire classroom groups in special education classes and regular classes from white middle-class areas and from all black poverty areas ranging from the first grade to junior high school were studied. The classroom teacher in each case acted as the experimenter and as an observer. Various means of recording behaviors were used and reliability of observation was checked by an outside observer, another teacher, a teacher-aide, a student, or by using a tape recorder. Observation sessions varied from 15 min to an entire school day. After baseline rates were obtained, extinction of inappropriate disputing or talking-out behaviors and reinforcement of appropriate behavior with teacher attention, praise and in some cases a desired classroom activity or a surprise at the end of the week brought a decrease in undesired verbalizations. A reversal of contingencies brought a return to high levels of inappropriate talking with a return to low levels when reinforcement for appropriate talking was reinstated. The experiments demonstrated that teachers in a variety of classroom settings could obtain reliable observational records and carry out experimental manipulations successfully using resources available in most schools.     

The effect of bulbocapnine administration on avoidance behavior

The Psychological Record -